PORTLAND, Maine — Nan Cumming, who has served as executive director of the land conservation group Portland Trails for 12 of its 20 years, will leave early next year to take the top job at the Maine Crafts Association.

Cumming, who oversaw the trail organization’s milestone acquisition of 68 scenic acres along the Presumpscot River almost nine years ago, will start as the craft group’s executive director on Feb. 1.

“That was a major accomplishment because it was our first real capital campaign, but also because it was really under threat of development,” Cumming recalled of the Presumpscot River preservation Monday to the Bangor Daily News. “If Portland Trails and the city hadn’t gotten in there when we did, it really would have been cut off to public access.”

But she said it will be hard to single out any favorite accomplishment during her time with Portland Trails, an organization that has protected about 200 acres of land in a mostly urban environment over two decades, conserving nearly 34 miles of trails for outdoor activity.

“It’s been a really wonderful 12 years, just seeing the organization grow and seeing the signs pop up,” she said. “It’s really satisfying, because the results of our work is right there before us. To go on a walk in an area that I had some hand in preserving is very gratifying.

“I’m proud of my role here, but I also know I didn’t do it alone,” Cumming continued. “I’m part of a really wonderful team of staff and board members here.”

She said she looked forward to the new challenge offered by the Maine Crafts Association, which has its headquarters in Dover-Foxcroft and has a gallery space in West Gardiner. Cumming said she’ll continue to work from Portland when she takes the new position.

“I think it’s good to have new challenges and growth,” she said. “There’s so much talk about what makes Maine unique, and local crafters and artisans are really what make Maine unique. When people come to Maine, they don’t want what they can get back home in chain stores, they want Maine-made crafts. I’m excited about the work Maine fine craft artists are doing and the opportunity to promote the works of these artists.”

In an announcement issued by Portland Trails, the organization said it will post the job opening on Thursday to begin seeking a new executive director. The group listed its many successes with Cumming at the helm, including the establishment of its popular Portland Trails 10K: Trail to Ale race, the publishing of its first map and trail guide and protection of the Bayside Trail.

“We are deeply grateful for all that Nan has done for Portland Trails during her 12-year tenure,” read a group statement released Monday afternoon. “In that time, we have increased the trail network to almost thirty-five miles of connected walking and biking paths. We have expanded our coverage throughout Greater Portland by adding trails in Falmouth, Westbrook, and South Portland. And we launched the Schoolground Greening initiative to bring safe, natural playgrounds to Portland area schools.”